mod=998244353
M=(10**5)*3+1 
fac=[1]*M
ninv=[1]*M
finv=[1]*M
for i in range(2,M):
  fac[i]=fac[i-1]*i%mod
  ninv[i]=(-(mod//i)*ninv[mod%i])%mod
  finv[i]=finv[i-1]*ninv[i]%mod

def binom(n,k):
  if n<0 or k<0:
    return 0
  if k>n:
    return 0
  return (fac[n]*finv[k]%mod)*finv[n-k]%mod

N,B,W=map(int,input().split())
ans=0

for t,p,q in [[1,2,0],[2,3,1],[1,4,2]]:
  for c1 in range(B):
    x=B-1-c1
    y=N+1-W-c1-p
    c2=3*x-y
    c3=y-2*x
    if c2<0 or c3<0:
      continue
    ans+=t*binom(B-1,c1)*binom(B-1-c1,c2)%mod*binom(W+c3+q-1,c3+q-1)
    ans%=mod

print(ans)